JP4033116B2 - Optical switch device - Google Patents

Description

  The present invention relates to an optical waveguide switching device used for an optical fiber switch or the like, or an optical switch device used as a variable optical attenuator for appropriately attenuating optical input. More specifically, the present invention relates to a position detection technique for a movable body equipped with a light reflecting member that switches a light emission position.

  As an optical switch device for switching the coupling state between optical waveguides such as optical fibers, an optical waveguide type using a refractive index fluctuation due to heat of the optical fiber, a MEMS (Micro) using a micro optical element and a micro actuator by a semiconductor process, and the like. An electro mechanical system type is known (for example, Patent Document 1).

  The former optical waveguide type optical waveguide switching device has a large optical loss due to coupling and branching of optical waveguide fibers. Moreover, in order to maintain the state after switching the optical waveguide, it is necessary to always supply power to the heater, and the life of the apparatus is relatively short. In addition, the MEMS type optical switch has a problem of high manufacturing cost because it uses a semiconductor process.

  Therefore, a right-angle prism mirror is directly opposed to an optical fiber array in which a common input optical waveguide and a plurality of output optical waveguides are arranged. A device for switching the coupling state between waveguides has been devised. This type of optical switch device includes, for example, a movable body on which a right-angle prism mirror is mounted, and a fixed-side member that supports the movable body with a suspension wire so that the movable body can move in the left-right direction and the up-down direction. The movable body is driven and controlled by the magnetic drive circuit, so that the optical waveguide is switched by moving to a desired position.

Here, a beryllium copper wire is generally used as the suspension wire.
JP 2002-250874 A

  In such a suspension wire type optical switch device, the suspension wire is bent when the movable body is moved, and this state is maintained. Moreover, the optical switch device may be used at a high temperature of 80 ° C. or higher, but beryllium copper used as a material for the suspension wire has a low melting point of 860 ° C. For this reason, if the suspension wire remains in a state where stress is applied for a long time in a high temperature atmosphere, plastic deformation proceeds. When such a so-called “creep” occurs, the right-angle prism mirror is displaced in the X direction. As a result, there is a problem that the coupling state between the input optical waveguide and the output optical waveguide changes.

  In view of the above problems, an object of the present invention is to provide an input optical waveguide and a desired output optical waveguide in a suspension wire type optical switch device even if the light reflecting member is displaced due to the occurrence of creep in the wire. An object of the present invention is to provide a configuration capable of reliably coupling a waveguide.

  In order to solve the above-described problem, in the present invention, when the directions orthogonal to each other are set to the X direction, the Y direction, and the Z direction, respectively, the predetermined position that reflects light incident from the Z direction and is shifted in the X direction. Light having a movable body on which a light reflecting member for emitting light is mounted, a fixed-side member that supports the movable body so as to be displaceable in at least the X direction, and drive means for driving the movable body in at least the X direction. The switch device further includes position detecting means for detecting the position of the movable body in the X direction.

Further, in the present invention, the drive means includes a drive coil for magnetically driving the movable body in the X direction on one side of the fixed side member and the movable body . A drive current in which an AC component is superimposed on a DC component is applied, and the position detection unit includes a position detection coil at a position close to the drive coil on the other side of the fixed side member and the movable body. It is characterized by being. Therefore, since position detection can be performed using the drive coil, it is only necessary to newly add a position detection coil as the position detection means, so that the optical switch device can be miniaturized.

  In the present invention, when the drive means includes a pair of the drive coils, the position detection means includes a pair of the position detection coils opposed to each of the pair of drive coils, and the pair of position detections. The position of the movable body in the X direction can be detected based on the differential output of the detection output of the coil. With this configuration, even if the output of each position detection coil changes due to the environmental temperature or the like, the pair of position detection coils change in the same manner, so that accurate position detection can always be performed even if there is a temperature change or the like. it can.

  In the present invention, in a state where the movable body is at the origin position, each magnetic center of the pair of position detection coils is located either on the inner side or the outer side with respect to the magnetic centers of the pair of drive coils. Preferably it is. With this configuration, as the movable body is driven, the magnetic center of one position detection coil approaches the magnetic center of one drive coil, while the magnetic center of the other position detection coil is the magnetic center of the other drive coil. It will be away from. Therefore, since the characteristics of the detection output are reversed between one position detection coil and the other position detection coil, the position of the movable body can be detected by obtaining the differential output of the pair of position detection coils. Here, when both of the magnetic centers of the pair of position detection coils are positioned inside the magnetic centers of the pair of drive coils, there is an advantage that the linearity of the differential output can be ensured.

  In the present invention, the AC component superimposed on the drive current is preferably 200 kHz to 300 kHz. With such a high-frequency component, position detection can be performed without affecting the drive of the drive coil even when applied to the drive coil.

  Since the optical switch device of the present invention has position detecting means for detecting the position of the movable body, the result of detecting the position of the movable body can be fed back. Therefore, even when the movable body is displaced due to the suspension wire creep or the like, the input optical waveguide and the desired output optical waveguide can be reliably coupled.

  An optical switch device to which the present invention is applied will be described with reference to the drawings.

(Basic principle of optical switch device)
FIG. 1 is an explanatory view schematically showing the basic principle of the optical switch device of the present invention. In the following description, directions orthogonal to each other will be described as an X direction, a Y direction, and a Z direction, respectively.

  In FIG. 1, the optical switch device 1 of the present embodiment includes an 8-channel light in which one input side optical fiber 20 extending in the Z direction and eight output side optical fibers 21 are arranged in parallel along the X direction. It is a switch device and can guide light output from the input side optical fiber 20 to any of the eight output side optical fibers 21. Here, in the optical fiber array 3 composed of the input side optical fiber 20 and the output side optical fiber 21, the optical fibers 20 and 21 are arranged at equal intervals at a pitch of 250 μm in the X direction.

  In the optical switch device 1 of this embodiment, a prism mirror driven in the X direction is used as a light reflecting member for reflecting the light incident from the Z direction and emitting it from a predetermined position shifted in the X direction toward the Z direction. 10 is used. The prism mirror 10 includes an inclined surface 101 where light enters and exits from the Z direction, a first reflecting surface 102 that reflects light incident from the inclined surface 101 in the X direction, and an orthogonal to the first reflecting surface 102. , A right-angle prism including a second reflecting surface 103 that reflects light reflected from the first reflecting surface 102 toward the inclined surface 101, with the inclined surface 101 (opening side) facing the optical fiber array 3. ing. The light emitted from the input side optical fiber 20 is collimated by the collimating lens 22 before entering the prism mirror 10. Although not shown, a collimating lens is also disposed between the eight output side optical fibers 21 and the inclined surface 101 of the prism mirror 10.

  In the optical switch device 1 configured as described above, for example, it is assumed that the prism mirror 10 is fixed at a position indicated by a solid line. In this state, the light emitted from the input-side optical fiber 20 enters the prism mirror 10, and the path of the optical path L1 that reflects the first inclined surface 102 and the second inclined surface 103 in the prism mirror 10 at 90 degrees, respectively. , And is guided to the output-side optical fiber 21a at the rightmost end of the output-side optical fiber 21.

  Next, when the output side optical waveguide is switched from the output side optical fiber 21a to the output side optical fiber 21f located at the sixth position from the right side, the prism mirror 10 is driven in the X direction and moved to the position indicated by the dotted line. Let When the prism mirror 10 is moved in this way, the reflection position of the light emitted from the input side optical fiber 20 on the first inclined surface 102 and the second inclined surface 103 in the prism mirror 10 moves, and the light path L2 is moved. Then, it is guided to the output side optical fiber 21f.

  Here, in the optical fiber array 3, the input side optical fiber 20 and the output side optical fiber 21 are arranged at a pitch of 250 μm, so that the prism mirror 10 has the input side optical fiber 20 and the output side optical fiber 21. It is moved in the X direction in units of 125 μm corresponding to ½ times the pitch.

(Overall configuration of optical switch device)
2A, 2B, 2C, and 2D are a plan view, a front view, a side view, and a rear view of an optical switch device to which the present invention is applied. FIG. 3 is a cross-sectional view of the optical switch device taken along line AA ′ in FIG. FIG. 4 is a perspective view of the optical switch body mounted on the front half of the optical switch device according to the present invention as viewed obliquely from the rear side with the pressing member removed.

  As shown in FIGS. 2 and 3, the optical switch device 1 of the present invention has a flat and substantially rectangular parallelepiped shape, and a movable body 2 on which a prism mirror 10 is mounted is attached to the upper side of the optical switch device 1. The pressing member 41 is energized. An optical switch body 100 using the principle shown in FIG. 1 is mounted on the front half of the optical switch device 1. In the rear half of the optical switch device 1, a clamping magnetic drive circuit 45 constituting the clamp mechanism 40 is mounted together with a pressing member 41 that covers the upper side of the optical switch device 1. Supports 47 and 48 stand up from the bottom plate 14 of the fixed member 13 on both the left and right sides of the center position of the optical switch device 1, and swing fulcrums 50 and 51 of the pressing member 41 are provided at the ends of the support 47 and 48. It has been.

(Configuration of optical switch body)
As shown in FIGS. 2, 3 and 4, in the front half of the optical switch device 1, the optical switch body 100 includes a movable body 2 on which a prism mirror 10 indicated by a dotted line is mounted, and this movable body 2 as X, The stationary member 13 is supported by the suspension wire 4 so as to be movable in the Y direction, and a magnetic drive circuit that drives the movable body 2 in the X and Y directions.

  The movable body 2 has a frame portion 16 on which a prism mirror mounting portion 11 on which a prism mirror 10 is mounted, a driving coil 5 for driving in the Y direction, and a pair of driving coils 6 and 7 for driving in the X direction are mounted. It consists of. The prism mirror 10 is mounted at the center position in the X direction of the prism mirror mounting portion 11 with the inclined surface 101 facing forward.

  V-grooves 30 are continuously formed on the lower surface 11a of the prism mirror mounting portion 11 at a constant pitch over the entire range in the X direction (see FIG. 7). In this embodiment, since the pitch of the optical fiber array 3 is 250 μm, the pitch of the V-shaped grooves 30 is 125 μm correspondingly. Further ahead of the prism mirror mounting portion 11 is a region in which the optical fiber array 3 described with reference to FIG. 1 is disposed, and light emitted from the input side optical fiber 20 of the optical fiber array 3 and the optical fiber array 3. The optical axes emitted to the output-side optical fiber 21 are indicated by an optical axis Lin and an optical axis Lout.

  The fixed member 13 includes a bottom plate 14 that defines the bottom surface of the optical switch device 1 and a support base 12 attached to the bottom plate 14. A pair of drive magnets 81 and 82 and a yoke 9 for driving the movable body 2 in the X direction and the Y direction are mounted on the bottom plate 14. The drive magnet 81 is located inside the drive coil 5. The drive magnet 82 faces the drive coils 6 and 7 outside the drive coil 5. In the bottom plate 14, a fixed portion 15 that receives the movable body 2 is provided immediately below the prism mirror mounting portion 11 of the movable body 2.

  The fixed portion 15 has a dimension that is longer in the X direction than the lower surface 11 a of the prism mirror mounting portion 11. A V-shaped groove 31 (unevenness) that meshes with a V-shaped groove 30 (unevenness) formed on the lower surface 11 a of the movable body 2 is continuously formed on the upper surface 15 a of the fixed portion 15. The pitch of the V-shaped grooves 31 is also 125 μm. Here, the moving path of the movable body 2 in the X direction, the lower surface 11a of the prism mirror mounting portion 11, and the upper surface 15a of the fixed portion 15 formed on the fixed side member 13 are formed in parallel to each other.

  As shown in FIG. 4, in the fixed side member 13, a total of four suspension wires 4 are fixed to the fixed side from the support base 12, each of the left and right two supporting the movable body 2 from the left and right sides. The member 13 extends in parallel with the bottom plate 14. A control circuit (not shown) for the drive coils 5, 6, and 7 mounted on the movable body 2 is disposed on the support base 12 side and controls the drive coils 5, 6, and 7 mounted on the movable body 2. Energization is performed using the suspension wire 4 as an energization line. In the case of this embodiment, four suspension wires 4 are energized, but four or more suspension wires 4 may be used as necessary, or less.

  The drive magnets 81 and 82 generate magnetic fluxes that are linked to the drive coil 5 of the movable body 2, and pair with the drive coil 5 to drive a magnetic drive circuit that drives the movable body 2 in the Y direction. It is composed. Therefore, by energizing the drive coil 5, a thrust in the Y direction is applied to the movable body 2. Further, the drive magnets 81 and 82 generate magnetic fluxes that interlink with the drive coils 6 and 7, and pair with the drive coils 6 and 7 to drive the movable body 2 in the X direction. A drive circuit is configured. Accordingly, by energizing the drive coils 6 and 7, a thrust in the X direction is applied to the movable body 2.

(Clamp mechanism configuration)
FIG. 5 is a perspective view of the magnetic drive circuit for clamping mounted on the rear half of the optical switch device of the present invention as viewed obliquely from above with the pressing member removed. FIG. 6 is an explanatory diagram showing a magnetic flux generated in the magnetic driving circuit for clamping.

  2, 3, and 5, in the optical switch device 1 of the present embodiment, the clamp mechanism 40 includes a plate-like pressing member 41 that urges the movable body 2 and fixes the movable body 2 to the fixed-side member 13, and the movable body 2. Is constituted by a torsion spring 60 that always urges the pressing member 41 toward the fixed side member 13 and a clamp magnetic drive circuit 45 that drives the pressing member 41.

  The pressing member 41 includes a top plate 42 that covers the top of the optical switch body 100 and extends to the rear of the optical switch device 1, and left and right side plates 43 that cover the side surfaces of the optical switch body 100. 14 is supported by swinging fulcrums 50 and 51 provided at the ends of the left and right support columns 47 and 48 rising from 14. Further, a semicircular pressing protrusion 44 projects downward from the front end of the top plate 42. The pressing member 41 serves as a housing of the optical switch device 1 together with the bottom plate 14 of the fixed side member 13 extending to the rear of the optical switch device 1 and has a function of protecting the optical switch body 100 from the outside. .

  In the left and right support columns 47 and 48 of the bottom plate 14, a torsion portion 61 of a torsion spring 60 is attached to the center position in the height direction, and two end portions 62 and 63 extending above and below the torsion portion 61 are optical switch devices. 1 extends backward. Of the two end portions 62, 63, the tip end of the end portion 62 is locked to a slightly rear position of the top plate 42 of the pressing member 41, and the tip end of the end portion 63 is related to a slightly rear position of the bottom plate 14. It has been stopped. Accordingly, the torsion spring 60 pushes the rear end portion of the pressing member 41 upward, and as a result, the pressing member 41 is slightly inclined forward with respect to the bottom plate 14. In this state, the pressing protrusion 44 of the pressing member 41 abuts on the upper end surface 11b of the prism mirror mounting portion 11, and the pressing member 41 presses and fixes the prism mirror mounting portion 11 toward the fixing portion 15 ( Clamped state). In this embodiment, the suspension wire 4 is designed not to bend in the Y direction in such a clamped state.

  The clamping magnetic drive circuit 45 is mounted on the first and second clamping magnets 70 and 71 attached to the pressing member 41 side and the bottom plate 14 side of the fixed side member 13 as described below. The clamping coil 72 and a clamping yoke 75 (back yoke) attached to the bottom plate 14 side.

  As shown in FIG. 3, a rectangular opening 420 is formed in the top plate 42 at the rear of the optical switch device 1, and further in the width direction (X direction) at a position near the rear end of the rear top plate 42. ) Are formed, and plate-like first and second clamping magnets 70 and 71 are attached thereto. Here, the first and second clamping magnets 70 and 71 protrude toward the fixed side member 13 with different poles facing each other.

  On the other hand, the bottom plate 14 of the fixed side member 13 is largely cut out at the center, and only the left and right edge portions 14a and 14b extend rearward. In this embodiment, the clamping coil 72 is mounted so as to straddle the left and right edges 14a and 14b. The clamp coil 72 is a rectangular tube-like coil whose long side extends in the X direction, and the coil opening 72 e faces the top plate 42 of the pressing member 41.

  A yoke support member 76 is attached to the bottom plate 14 so as to protrude inside the notch 73. The yoke support member 76 has a stepped portion 76a that is slightly bent downward in the Y direction and then extends in the Z direction. The clamping yoke 75 is held in a cantilevered state from the stepped portion 76a to the distal end side. . Therefore, the lower end portion of the clamping yoke 75 is located in the notch 73.

  The clamping yoke 75 has a U-shaped cross section having two upstanding walls 75a and 75b extending in parallel to each other and a bottom wall 75c connecting the upstanding walls 75a and 75b. Of these upright walls 75 a and 75 b, the upright wall 75 a faces the coil side 72 a with a predetermined gap outside the coil opening 72 e of the clamp coil 72, and the upright wall 75 b is connected to the clamp coil 72. The coil side 72a and the coil side 72b are opposed to each other inside the coil opening 72e.

  In the clamp magnetic drive circuit 45 configured as described above, the first clamp magnet 70 is located outside the coil opening 72e of the clamp coil 72 in the state where the optical switch device 1 is assembled. It is located between the upright wall 75a and the coil side 72a of the clamping coil 72. The second clamp magnet 71 is positioned between the upright wall 75 b of the clamp yoke 75 and the coil side 72 a of the clamp coil 72 inside the coil opening 72 e of the clamp coil 72.

  Therefore, the first and second clamping magnets 70 and 71 (magnet pair) are arranged so that different poles face each other and the clamping coil 72 is sandwiched between the inside and the outside of the coil opening 72e, and the clamping coil In each of the inner side and the outer side of the coil opening 72 e of 72, the upright walls 75 a and 75 b of the clamping yoke 75 are arranged as back yokes behind the clamping magnets 70 and 71.

  In the clamp mechanism 40 configured as described above, in the clamp magnetic drive circuit 45, the clamp magnets 70 and 71 and the clamp yoke 75 are provided with a clamp coil 72 as shown by an arrow Q as shown in FIG. A magnetic flux interlinking with the coil side 72a is generated, and this magnetic field is closed. Therefore, in the clamping mechanism 40, when the coil 72 for clamping is not energized, the rear end portion of the pressing member 41 is pushed upward by the torsion spring 76 as shown by the arrow F1, and as a result, the front end of the pressing member 41 The part presses the movable body 2 downward (clamped), but when the clamp coil 72 is energized, the clamping magnetic drive circuit 45 causes the rear end of the pressing member 41 to be as indicated by the arrow F2. It is pushed down against the torsion spring 76. As a result, the front end portion of the pressing member 41 is lifted and the downward pressing of the movable body 2 is released (unclamped state).

(Description of optical waveguide switching operation)
FIG. 7 is an explanatory diagram showing the positional relationship between the movable body and the stationary member when performing an operation of switching the optical waveguide in the optical switch device to which the present invention is applied.

  As shown in FIG. 7A, at the initial fixed position (origin position / stationary position), the movable body 2 is in a clamped state in which the movable body 2 is urged and fixed by the pressing member 41 toward the fixed side member 13. The V-shaped grooves 30 and 31 formed on the lower surface 11a of the prism mirror mounting portion 11 and the upper surface 15a of the fixing portion 15 are in an engaged state.

  In order to perform the operation of switching the optical waveguide from this state, first, the clamp coil 72 is energized. As a result, as shown in FIG. 7B, the pressing member 41 swings around the swing fulcrums 50 and 51 so that the front end portion is lifted against the urging force of the torsion spring 60, and the pressing member A pressing protrusion 44 located at the tip of 41 is lifted from the movable body 2. Then, the drive coil 5 is energized to float the movable body 2 in the Y direction against the urging force of the suspension wire 4. The energization of the drive coil 5 may be performed simultaneously with the energization of the clamp coil 72. Due to the lifting operation of the movable body 2, the suspension wire 4 is bent in the Y direction.

  Next, the drive coil 6 is energized, and the movable body 2 is moved in the X direction as shown in FIG. When the movable body 2 has moved to a desired position in the X direction, as shown in FIG. 7D, the energization to the drive coil 5 is stopped and the movable body 2 is moved by the elastic return force of the suspension wire 4. Is sunk downward in the Y direction.

  Next, the energization to the clamping coil 72 is stopped. As a result, as shown in FIG. 7 (e), the pressing member 41 is in a clamped state in which the movable body 2 is urged downward in the Y direction by the urging force of the torsion spring 60 and pressed against the stationary member 13. . At this time, the V-shaped groove 30 formed in the movable body 2 and the V-shaped groove 31 formed in the stationary member 13 are engaged with each other, and the movable body 2 is positioned in the X direction.

  Thereafter, energization of the drive coil 6 is stopped. Thereby, the switching operation of the optical waveguide is completed. Accordingly, the light incident on the prism mirror 10 from the incident side optical fiber 20 is emitted to the predetermined output side optical fiber 21 via the prism mirror 10.

(Configuration of position detecting means for the movable body 2)
FIGS. 8A and 8B are a perspective view and a side view of the position detecting means as viewed obliquely from above in the optical switch device to which the present invention is applied. FIGS. 9A and 9B are explanatory views showing the positional relationship of the position detecting means when performing an operation of switching the optical waveguide in the optical switch device to which the present invention is applied.

  As will be described below with reference to FIGS. 8A and 8B and FIGS. 9A and 9B, the optical switch device 1 of the present embodiment uses the drive coils 6 and 7, A detecting means for detecting the position of the movable body 2 in the X direction is configured.

  First, in this embodiment, as shown in FIGS. 8A and 8B and FIGS. 9A and 9B, the space between the drive magnets 81 and 82 is defined as a magnetic gap G, and the movable body 2 When viewed from the Z direction, the horizontal sides 6a, 6b, 7a and 7b of the drive coils 6 and 7 are substantially centered in the X direction, and both edges of the magnetic gap G in the X direction (drive magnet 81). , 82 are set so that the width dimensions (W) of the magnets 81 and 82 match each other. Further, when the movable body 2 is at the origin position, the height dimensions of the drive magnets 81 and 82 are such that the horizontal sides 6a, 6b, 7a and 7b of the drive coils 6 and 7 are located in the magnetic gap G in the Y direction. (H) is set.

  Here, the drive coils 6 and 7 are wound in opposite directions, and the drive force in the X direction is generated by the current flowing through the vertical sides 6c and 7c inside the drive coil 6 and 7 in the X direction. At this time, the driving force in the Y direction is also generated by the current flowing in the upper and lower horizontal sides 6a, 6b, 7a, 7b of the driving coils 6, 7, but it is canceled because it is upside down, and the movable body 2 is driven in the Y direction. Not.

  Corresponding to such a magnetic drive circuit, the position detection means 19 of the present embodiment is provided between the two drive coils 6 and 7 and the drive magnet 82 so as to face two of the two drive coils 6 and 7. Position detection coils 17 and 18 are provided, and these position detection coils 17 and 18 are fixed to a surface of the drive magnet 82 facing the drive coils 6 and 7. Here, when the state in which the movable body 2 is at the origin position is viewed from the Z direction, the center position in the X direction of the region sandwiched between the vertical sides 17c, 18c inside the X direction of the position detection coils 17, 18 and the drive magnet The center position in the X direction of 82 coincides, and the positions of the outer edges of the vertical sides 17d and 18d on the outer side in the X direction coincide with the positions of both end edges in the X direction of the drive magnet 82. Further, the center position in the X direction of the vertical sides 17c and 18c inside the X direction of the position detection coils 17 and 18 and the center position in the X direction of the vertical sides 6c and 7c inside the X direction of the drive coils 6 and 7 are the same. In the state where the magnetic centers of the drive coils 6 and 7 coincide with the vertical sides 17d and 18d outside the X direction of the position detection coils 17 and 18, and the movable body 2 is at the origin position, a pair of position detection coils Each of the magnetic centers 17 and 18 is located inside the magnetic centers of the pair of drive coils 6 and 7.

  In the position detection means 19 of this embodiment, as shown in FIG. 9, two position detection coils 17 and 18 are connected in series, and the terminal A and the terminal C are drawn from each of the position detection coils 17 and 18, An intermediate tap B is drawn from a connecting line that connects the position detection coils 17 and 18.

  The drive coils 6 and 7 are also connected in series. Terminals D and E are drawn out from the drive coils 6 and 7, respectively, and these terminals D and E are connected to a DC power source for driving the movable body 2. Has been. In this embodiment, the drive coils 6 and 7 are configured so that a drive current in which an AC component as a position detection signal is superimposed on a DC component is applied to the DC components via the terminals D and E. The frequency is set to a high frequency region of about 200 to 300 kHz that does not affect the driving of the driving coils 6 and 7 even when applied to the driving coils 6 and 7.

(Detection operation)
10 (a) to 10 (e) respectively show an optical switch device to which the present invention is applied, from the position detection coil 17 in a state before the movable body 2 moves after a voltage is applied to the drive coils 6 and 7. FIG. It is explanatory drawing which shows each waveform of output, DC output after detecting this output, the output from the position detection coil 18, DC output after detecting this output, and the difference output of two DC signals. FIGS. 11A to 11E show the position detection coil 17 after the movable body 2 has moved after the voltage is applied to the drive coils 6 and 7 in the optical switch device to which the present invention is applied. FIG. 6 is an explanatory diagram showing respective waveforms of an output from, a DC output after detecting this output, an output from the position detection coil 18, a DC output after detecting this output, and a difference output of two DC signals.

  First, before energizing the drive coils 6 and 7 and moving the movable body 2, as shown in FIG. The vertical sides 17d and 18d on the outside in the X direction coincide with each other. At this time, the center side end portions of the vertical sides 17c and 18c on the inner side in the X direction of the position detection coils 17 and 18 also coincide with the center side end portions of the vertical sides 6c and 7c on the inner side in the X direction of the drive coils 6 and 7, respectively. ing. That is, the magnetic centers of the position detection coils 17 and 18 are both located inside the magnetic centers of the pair of drive coils 6 and 7, and the distance between the magnetic centers of the position detection coil 17 and the one drive coil 6 is The distance between the position detection coil 18 and the magnetic center of the other drive coil 7 is the same. Therefore, AC components having the same waveform are detected between the terminals A and B of the position detection coil 17 and between the terminals B and C of the position detection coil 18, respectively, as shown in FIGS. 10 (a) and 10 (c). . Such an AC current waveform is once detected by a detection circuit (not shown) and converted into a DC output as shown in FIGS. 10B and 10D, respectively. Accordingly, the differential DC output obtained through the differential amplifier (not shown) becomes 0 V as shown in FIG.

  From this state, when the movable body 2 is driven in the X direction, the magnetic center of the position detection coil 17 moves away from the magnetic center of the drive coil 6 and the magnetic force of the position detection coil 18 as shown in FIG. The center approaches the magnetic center of the drive coil 7. At this time, since the magnetic center of the position detection coil 17 moves away from the magnetic center of the drive coil 6, the output between the terminals A and B decreases as shown in FIG. On the contrary, since the magnetic center of the position detection coil 18 approaches the magnetic center of the drive coil 7, the level of the output increases as shown in FIG. Such an AC current waveform is detected by a detection circuit, and converted into a DC output as shown in FIGS. 11B and 11D, respectively. Therefore, the differential DC output obtained through the differential amplifier shows a positive predetermined value as shown in FIG. Therefore, the position of the movable body 2 can be finally detected by comparing the differential DC output with a table obtained in advance for the relationship between the differential DC output and the amount of movement of the movable body 2. .

  Here, since the AC output is converted into a DC output and then the differential output is obtained, it is not necessary to consider the asynchronousness of the AC waveform. Therefore, there is no need to increase the component accuracy and assembly accuracy or to add a correction circuit separately in order to avoid AC waveform asynchronization, and the difference between both outputs can be accurately obtained by the differential amplifier.

(Effect of this embodiment)
As described above, the optical switch device 1 according to the present invention has the position detection means 19 for detecting the position of the movable body 2 as a mechanism for compensating for the displacement caused by the creep deformation of the suspension wire 4. ing. Therefore, the position of the movable body 2 can be detected even if the prism mirror 10 is displaced due to creep as a result of the suspension wire 4 being kept stressed for a long time in a high temperature atmosphere. Since the result can be fed back, the input optical fiber 20 and the desired output optical fiber 21 can be reliably coupled.

  In this embodiment, since the drive coils 6 and 7 are driven by a drive current in which an AC component is superimposed on a DC component, the position detection coils 17 and 18 perform position detection using this AC component. For this reason, since the drive coils 6 and 7 can be used as a part of the position detection means 19, it is only necessary to add the position detection coils 17 and 18 in configuring the position detection means 19, and the optical switch device 1 can be downsized. You can plan.

  Furthermore, in this embodiment, since the position detection is performed by obtaining the differential output of the detection output from the position detection coils 17 and 18 facing the drive coils 6 and 7, the output of each position detection coil 17 and 18 is the temperature. Even if it changes due to the change, the outputs from the position detection coils 17 and 18 change similarly. Therefore, since the influence of temperature is canceled, accurate position detection can always be performed even if there is a temperature change.

  Furthermore, in this embodiment, in the state where the movable body 2 is at the origin position, each magnetic center of the position detection coils 17 and 18 is located inside with respect to each magnetic center of the pair of drive coils 6 and 7. . For this reason, when the movable body 2 moves, the magnetic center of one of the position detection coils 17 and 18 approaches the magnetic center of the corresponding drive coil 6 or 7, while the other of the position detection coils 17 and 18. The magnetic center of the position detection coil is moved away from the magnetic center of the corresponding drive coils 6 and 7. Accordingly, since the change in detection output between the position detection coil 17 and the position detection coil 18 is opposite, the position of the movable body 2 can be detected with high accuracy from the differential output of both the position detection coils 17 and 18. In addition, since both of the magnetic centers of the position detection coils 17 and 18 are positioned on the inner side of the magnetic centers of the pair of drive coils 6 and 7, there is an advantage that the linearity of the detection output is high.

(Other embodiments)
In the above embodiment, the position detection coils 17 and 18 are connected to each other by a connection line, and the intermediate tap B is output from the connection line. However, the position detection coils 17 and 18 are not necessarily connected. It is not necessary to use it. That is, the position detection coil 17 and the position detection coil 18 may not be connected to each other, but may be independent coils, and detection outputs may be obtained from both ends of each coil.

  In the above embodiment, the winding direction and the number of windings of the position detection coils 17 and 18 are not mentioned, but they may be wound in opposite directions or in the same direction. . That is, as in the above embodiment, when the output between the terminals A and B and the output between the terminals B and C are input to the detection circuit and then converted into a DC output, the AC waveform is asynchronous. Since there is no relation, the winding direction and the number of turns of the position detection coil are not questioned.

  Further, in the stationary state of the movable body 2, the ends of the vertical sides 17d and 18d outside the X direction of the position detection coils 17 and 18 are made to coincide with the respective ends of the drive magnet 82 in the X direction. There is no need to match. However, a configuration in which the position detection coils 17 and 18 and the magnetic centers of the drive coils 6 and 7 are matched, or one of the magnetic centers of the position detection coils 17 and 18 is connected to the magnetic center of the drive coils 6 and 7. In the configuration in which the other of the magnetic centers of the position detection coils 17 and 18 is disposed outside the magnetic center of the drive coils 6 and 7, the position detection coils 17 and 18 are moved as the movable body 2 moves. When the characteristics of the detection output obtained from the above change similarly, the differential outputs obtained from the position detection coils 17 and 18 become 0V. In the case of such an arrangement relationship between the position detection coils 17 and 18 and the drive coils 6 and 7, position detection becomes impossible. Therefore, various layouts are appropriately adopted except for such an arrangement relationship. can do.

  Further, in the above embodiment, the output between the terminals A and B and the output between the terminals B and C are first input to the detection circuit and converted into a DC output, and then the difference between the two outputs is converted by the differential amplifier. However, it may be configured in reverse. However, in this case, an accurate differential DC output cannot be obtained if there is a deviation in the waveform.

  Since the optical switch device of the present invention has position detecting means for detecting the position of the movable body, the result of detecting the position of the movable body can be fed back. Therefore, even when the movable body is displaced due to the suspension wire creep or the like, the input optical waveguide and the desired output optical waveguide can be reliably coupled.

It is the figure which represented typically the principle of the optical waveguide switching device with which this invention is applied. (A), (b), (c), (d) is the top view of the optical switch apparatus to which this invention is applied, a front view, a side view, and a rear view. It is sectional drawing of the optical switch apparatus in the AA 'line of Fig.2 (a). In the optical switch apparatus to which this invention is applied, it is the perspective view which looked at the optical switch main body mounted in the front half from the diagonally back in the state which removed the press member. In the optical switch device to which the present invention is applied, it is the perspective view which looked at the magnetic drive circuit for clamp mounted in the half after that from the slanting upper part in the state where the pressing member was removed. It is explanatory drawing which shows the direction of the magnetic flux which generate | occur | produces in the magnetic drive circuit for clamping in the optical switch apparatus to which this invention is applied. In the optical switch device to which the present invention is applied, it is an explanatory diagram showing the positional relationship between the movable body and the stationary member when performing the operation of switching the optical waveguide. (A), (b) is the perspective view and side view which looked at the position detection means from diagonally upward in the optical switch apparatus to which this invention is applied. (A), (b) is explanatory drawing which shows the positional relationship of the position detection means at the time of performing the operation | movement which switches an optical waveguide in the optical switch apparatus to which this invention is applied. (A)-(e) respectively detected the output from the position detection coil in the state before applying a voltage to a drive coil, and before a movable body moved in the optical switch apparatus to which this invention was applied. It is explanatory drawing which shows each waveform of DC output after this, the output from a position detection coil, DC output after detecting this output, and the difference output of two DC signals. (A) to (e), respectively, in the optical switch device to which the present invention is applied, after applying a voltage to the drive coil and then moving the movable body, the output from the position detection coil, and after detecting this output It is explanatory drawing which shows each waveform of DC output, the output from a position detection coil, DC output after detecting this output, and the difference output of two DC signals.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical switch apparatus 2 Movable body 3 Optical fiber array 4 Suspension wire 5, 6, 7 Drive coil 10 Prism mirror 12 Support base 13 Fixed side member 15 Fixed part 17, 18 Position detection coil 19 Position detection means 20 Input side optical fiber 21 Output side optical fibers 30 and 31 V-shaped groove 40 Clamp mechanism 41 Press member 44 Press protrusion 45 Clamp magnetic drive circuit 60 Torsion spring (biasing member)
70, 71 Clamping magnet 72 Clamping coil 81, 82 Drive magnet 100 Optical switch body

Claims (4)

When the directions perpendicular to each other are the X direction, the Y direction, and the Z direction,
A movable body on which a light reflecting member for reflecting light incident from the Z direction and emitting it from a predetermined position shifted in the X direction is mounted, and a fixed-side member that supports the movable body so as to be displaceable at least in the X direction. And an optical switch device having a driving means for driving the movable body in at least the X direction,
Furthermore, it has a position detecting means for detecting the position in the X direction of the movable body,
The drive means includes a drive coil for magnetically driving the movable body in the X direction on one side of the fixed member and the movable body, and an AC component is superimposed on a DC component in the drive coil. Drive current is applied,
The optical switch device, wherein the position detection means includes a position detection coil at a position close to the drive coil on the other side of the fixed side member and the movable body . In Claim 1, the said drive means is equipped with a pair of said drive coils,
The position detection means includes a pair of the position detection coils facing each of the pair of drive coils, and based on the differential output of the detection output from the pair of position detection coils, the X direction of the movable body An optical switch device that detects the position of the switch. 3. The magnetic center according to claim 2, wherein each of the magnetic centers of the pair of position detection coils is located inside or outside of the magnetic centers of the pair of drive coils in a state where the movable body is at the origin position. the light switch device, characterized in that are. 4. The optical switch device according to claim 1, wherein the AC component is 200 kHz to 300 kHz . 5.

Images